If the person in the figure wants his shadow to be 3 feet long, how far should he move and in what direction?

See attached photo.

sorry this is not chemistry I clicked the wrong subject

3 2/3 ft to the right

Explanation:

The picture of the question in the attached figure N 1

To better understand the problem see that attached figure with letters N 2

we know that

If two figures are similar, then the ratio of its corresponding sides is proportional

In this problem

Triangle A.D.F is similar to Triangle B.D.E ----> by AA Similarity Theorem

so

we have

substitute

solve for E.D

E.D is the length of the shadow

so

The person should move to the right x feet

convert to mixed number

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.